1. Field of the Invention
The present invention relates to a warming apparatus for use during sleep and more particularly to such a warming apparatus which is constructed to allow easy temperature adjustment while the warming apparatus is in operation.
2. Description of the Prior Art
Description will be made of an electric blanket by way of an example of a conventional warming apparatus for use during sleep. When a person goes to sleep, they use an electric blanket by setting an adjusting dial or temperature setting means to a high temperature setting for about 1 hour for preheating the bed, and then, after the bed has been warmed sufficiently, changing the setting of the adjusting dial or the temperature setting means to a lower setting which provides an appropriate lower temperature. Now, it is frequently the case, particularly with a person who feels chilly and unsatisfied with the present dial setting, to reset the adjusting dial to a high dial setting to raise the temperature of the blanket to warm their body rapidly. When such a high dial setting is selected, however, it is necessary for them to keep awake until their body has been warmed and then to restore the dial setting to a proper temperature setting after the lapse of a suitable time period. In most cases, however, the person falls asleep leaving the high dial setting as it is, and the dial setting is lowered only after they are awakened by an excessively high temperature. This is extremely unpleasant for a sleeper who desires to have a comfortable sleep.
To correct this problem, one can use a so-called "high" start method. According to this method, when a "high" start switch disposed in a controller of an electric blanket is closed, even if the dial setting remains at a normal setting suitable for sleeping, the blanket temperature is once raised to a "high" temperature and then the blanket temperature is automatically lowered to the temperature corresponding to the preset dial setting, thereby facilitating a dial operation for the purpose of preheating. It may be considered to use this "high" start switch method for recovering the temperature of a sleeper's body which has been lowered by leaving their bed. However, the use of this method has a disadvantage in that once the blanket temperature is raised to the "high" temperature the sleeper is exposed to a high bed temperature for a time. On the other hand, when the room temperature is high or when the body of a person has been warmed sufficiently because of drinking, bathing or the like, they often feel that the bed preheated by the electric blanket is too hot, and in this case will adjust the dial setting to a lower setting before going to sleep. Therefore, at dawn they will be awakened by the cold and will have to readjust the dial setting. Also, there is a further disadvantage. Since it is difficult for an aged person to read letters on a dial without using glasses, they are obliged to adjust the dial setting only by feel and hence there may result an excessively high or low dial setting, thereby making it difficult to have an appropriate bed temperature.